Development of low-damage low-temperature surface modification technique using laser detonation-induced broad atom beams

本研究旨在开发利用激光爆轰超音速原子束的低损伤表面改性新技术。结果表明，即使在室温下，5 eV原子氧束也能氧化端氢Si（001）表面。这是由于超过80%的平动能从撞击原子转移到表面原子。整体的氧化物生长遵循线性-抛物线关系，这与观察到的Si高温氧化相似。初始的线性生长受氧化剂的反应极限的支配，而抛物线型生长受氧化膜内体积扩散的支配。实验还证明了原子束照射可以控制聚合物的表面自由能（或润湿性）。根据实验结果，确定了激光爆轰超声速束诱导表面改性的潜在优势。

This study aims at developing the new low-damage surface modification technique using laser detonation supersonic atoms beams. It was made clear that the hydrogen-terminated Si (001) surface can be oxidized by 5 eV atomic oxygen beam even at room temperature. This is due to the fact that more than 80 % of the translational energy was transferred from the impinging atom to the surface atom. The overall oxide growth follows linear-parabolic relationship that is similar to that observed high-temperature oxidation of Si. The initial linear growth was governed by the reaction-limit of oxidant, whereas parabolic one was due to volume diffusion inside the oxide film. It was also demonstrated that the surface free energy (or wettability) of polymer could be controlled by atom beam exposures. From the experimental results obtained in this study, potential advantages of the laser detonation supersonic beam-induced surface modification were identified.